Nerve Biopsy--Is it worth the risk?

     I have had on/off burning pain in legs/arms/shoulders/back/neck, with some numbness, for a few years.  EMG's, Evokes, MRI's, blood tests all return "normal" --no nerve damage seems to be found.  I am a 35yr old male, non-diabetic and in otherwise good health.
     Neurologist wants to perform a nerve biopsy to see if PN present--to come up with a poss. diagnosis.  Is a biopsy worth the risk and pain?  I have *no* muscle weakness or atropy.  Assuming I may have *only* sensory PN, since I believe such a biopsy extracts only *motor* nerves, would such a test show sensory nerve prbs?  Could such a test turn up negative yet I could still have sensory PN?  Could test results change current treatment of roulette wheel of trying various drugs (Neurontin, etc.) for pain?
   Lastly, how would the Cleveland Clinic rule out or confirm PN is my situation?   Thanks.
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Thanks for the question Alan. Sounds to me like a nerve biopsy is alittle dramatic in this case with what you have told me. It seems unlikely that it will provide an answer. If you did have only a senssory PN then it should show up on the EMG. A tests such as a QST (Quantitative sensory testing) will sometimes pick up sensory PN's missed by the conventional EMG. Pure sensory PN's are caused by certain diseases and those would need to be looked at and are beyond the scope of this forum. The standard nerve biopsy looks at the sural nerve which is a sensory not a motor nerve. I'm not conviced from your story that you have a PN and I would recommend an evaluation at CCF by one of our neuromuscular experts. Good luck.
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